overfuelling?? mk3 gti 8v?

[GTIsean]

hi guys i have just noticed that my mk3 gti 8v has started to drink alot more fuel than it should i getting 100 miles to 20 pounds of fuel, the only thing i have done is put a pipercross cone filter, just trying to find out if anyone would have any ideas to what might be the course of this, i was thinkin a long the lines of a sensor gone?? and what is the sensor that goes on the side of the air box could this be the problem? or maybe the air mass?
Anyhelp would be great cheers sean.

[daytona]

readin on here id get rid of the cone and put a panel filter in,with the airbox mod.Believe it give a better responce.Give the car a service and check for any air leaks on the intake and exhaust as this could push more fuel thru.but tbh,i find the car a bit over the top on fuel as well.i do a 40 mile run a day and find im fillin up every other day with £10-20 a time and thats stickin to national speed.

[GTIsean]

Think i'm going to have to do that as its costing a bomb to run lol.